Trump lashed out at the Times on Twitter Saturday, saying the paper had used "phony sources" and quoted a member of his staff "who doesn’t exist." But audio released Saturday, and reports backed up by other news outlets, point out that the source does, in fact, exist.

4. I've obtained audio of the WH press briefing. You can hear Raj Shah, Deputy Press Secretary, introduce Pottinger (along with the terms - which are standard) and then Pottinger makes the statement that POTUS says was never made. Lots of reporters in briefing room and on phone. pic.twitter.com/2gEYkRSyTv

Journalist Yashar Ali, who posted the audio to Twitter, identified the source as National Security Council official Matt Pottinger. In the clip, deputy press secretary Raj Shah introduces Pottinger at an on-background meeting and asks reporters to refer to Pottinger as "a senior White House official."

In a barrage of tweets Saturday morning, Trump attacked the article for suggesting disagreements within the administration on a diplomatic strategy for North Korea, and admonished the Times to use "real people, not phony sources."

Trump was referring to a Times article in which the paper reported that an official said it would be impossible to move forward with the canceled June 12 summit between Trump and North Korean leader Kim Jong Un due to time constraints.

Pottinger, the deputy assistant to the president for Asia, took questions on Trump's quick pivot on his plans for meeting with North Korea. The president told reporters on Friday that, despite his Thursday letter to Kim canceling the historic summit, the June 12 meeting set for Singapore could still take place.

Trump has repeatedly undermined the press since his presidential campaign. Earlier this week, "60 Minutes" correspondent Lesley Stahl said that Trump told her he attacks the press so no one will believe the negative stories written about him.

In an interview at the Deadline Club, Stahl said she met with the then-candidate in Trump Tower in July 2016.

“And at one point he started to attack the press, and it’s just me and my boss and him … he’s attacking the press and there were no cameras, there was nothing going on,” Stahl said.

"And I said, 'You know that is getting tired, why are you doing this? You are doing it over and over, it’s boring, it’s time to end that. You won the nomination, why do you keep hammering at this?' ”

“And he said, ‘You know why I do it? I do it to demean you all and discredit you all, so that when you write negative stories about me no one will believe you,’ ” Stahl said.